Generally, a laser includes a gain medium (e.g., a gas, liquid, solid, or plasma) and an energy supply. The gain medium often absorbs energy (e.g., optical radiation, electrical current, kinetic energy, thermal energy, etc.) from the energy supply. The energy may excite atoms in the gain medium until a population inversion occurs (i.e., a number of electrons in an excited state exceeds a number of electrons in a relatively lower energy state). If the population inversion occurs, the gain medium generally emits more photons than the gain medium absorbs. If an electromagnetic wave (e.g., visible light) interacts with the gain medium during the population inversion, the gain medium may amplify the electromagnetic wave, and the laser may output a laser pulse.